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Connie

Cullets are especially prevelant in 19th-century paperweights and in many paperweights that are mainland China-made. You'll find them in Boston & Sandwich and New England Glass Company antiques. There are even classic French weights with cullets in them. I rarely see cullets in weights by most contemporaries. Never saw one in a Rosenfeld or a Stankard or a Trabucco or a Tarsitano or a Kaziun or a Perthshire or D'Albret or modern Baccarats or contemporary St. Louis.

Cullets look like little bits of "rock" or a rocklike substance floating in the glass dome, sometimes close to the canes or lampwork setting, sometimes simply drifting about the glass. They are actually very tiny touches of glassmaking material that didn't quite melt or fuse.

I don't think that "cullet" is the correct term for the inclusions in paperweights or any glass for that matter.

The specks in a glass piece are either described as frit or sand inclusions or carbon inclusions if black specks. The sand inclusions are undissolved silica in the molten glass. The black specks are contaminants in the molten glass usually from flying ash or carbon desposits in the furnace.

Edited to correct typos due to extreme caffeine deficiency at time of posting. The IV is now connected and all is well :wink:

In today's terminology, cullets are those flecks of flotsom floating in the glass dome. Sotheby's and Christies have long described the floating specks as cullets in their catalogues. As have Selman and even Mrs. Bergstrom in her book superb 1940s book on paperweights.

And usage on eBay - from those savvy about the thingies - also give credence to the use of the word cullet. Frankly, and I hope this doesn't offend anyone, these flecks or cullets actually look like tiny boogers. Lord, I can't believe I just typed that. I'm laughing too hard. Oh well, we're all adults here.

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Perhaps the mistake was originated in the Bergstrom book? Just another example of wrong in print becoming part of collectors terminology. It is really up to writers to correct such malapropisms, or at least a competent technical editor should be used.

[By KevH - in connection with flaws in paperweights]2. Pieces of "Frit"

These appear as white or silvery irregular shaped lumps. Sometimes they can be quite large and easily noticeable from a distance. Others can hardly be seen. This is the result of crystalisation within the glass - another problem of temperature control or perhaps pieces from the ceramic pot getting mixed in the batch.

I have some weights with large pieces of "frit" and these fall into my category of "academically acceptable" even though they are visually imperfect. Depending on the current (or perceived) rarity of a design, I am sometimes prepared to pay reasonable sums for weights with a bit of "frit".

[By Adam D. - in response]Warning - the following will cause acute boredom but, KevH, you asked for it!

Kev - Your "pieces of frit". Nothing wrong with the term, meaning unmelted raw material - usually bits of sand. However, "frit" was only for some reason used by Pilkingtons - all the rest of us called it "batch". I haven't a clue why, in hindsight I like the Pilks word better.

However, Kev, anything crystallising out from an originally clear glass (usually by holding it in a specific temperature range too long) is called "devitrification" (don't blame me). Generically, any foreign body in the glass, whether devit., unmelted batch/frit or bits of furnace are simply called "stones" or, in a few obscure places in NE England, "salts".

I did warn you!

So, from Adam D. we can add "Stones" and "Salts" to the list of terms. And I have certainly heard of, and used myself, "stones" in connection with 'lumps of stuff' in a paperweight dome'.

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KevinH

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A cullet IS a piece of broken glass that is re-fed into the system to be re-melted and to become part of the glass process again. Sometimes these bits of glass never completely disappear and stay in the system as a teeny tiny bit floating in the liquidy glass and end up within the completed paperweight dome.

If it's a cullet at the start of the remelting process, then when it fades and melts and becomes molten, some bits still remain and stay coarse and/or hard. These are surviving bits of glass that were cullets and when they survive and stay under the dome, they are still cullets - SURVIVING BITS OF GLASS.

Cullet is one of the oldest terms in glassmaking and is waste or scrap glass. Due to the difficulties of starting the melt of the glass metal cullet is often added to trigger the process. Some studios use only cullet to save on raw material costs.

French is GroisilGerman is ScherbenItalian is Rottame di vetroCzech is Strepy

Frit is the finely ground coloured glass used for colouring the melt or adding to a worked piece by marvering or other methods. This US glass supplier also uses the term so it is common to English speaking countries http://www.system96.com/Pages/Frit.htmlCorning defines this further: Batch ingredients such as sand and alkali, which have been partially reacted by heating, but not completely melted. After cooling, frit is ground to a powder and melted. Fritting (or sintering) is the process of making frit.

Any other uses of these terms is likely to be erroneous and likely as not born in a poorly editted book for collectors. Other uses of these two words should be avoided to prevent further confusion.

Corning also provided the word for unwanted inclusions in glass as SCALE.

Scale An accidental inclusion in glass, consisting of corrosion products detached from the metal implements used to stir the batch or to form the object.